Circuit structure

ABSTRACT

The disclosure provides a circuit structure including a first flexible insulating layer, a plurality of wires, and a second flexible insulating layer. The wires are stacked in parallel on the first flexible insulating layer. The second flexible insulating layer is stacked on the wires and has at least one insulating-layer opening from which a part of at least one of the wires is exposed.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the priority benefits of U.S. provisional application Ser. No. 62/838,310, filed on Apr. 25, 2019, and China application serial no. 201911188272.8, filed on Nov. 28, 2019. The entirety of each of the above-mentioned patent applications is hereby incorporated by reference herein and made a part of specification.

BACKGROUND Field of the Disclosure

The disclosure relates to a circuit structure.

Description of Related Art

Flexible Printed Circuit (FPC) is a flexible printed circuit board made of polyimide or polyester film as the base. It has the characteristics of light weight, thin thickness, and good bendability. However, it is required to adopt exposure, development, and etching processes to form wiring in manufacturing the FPC, even simple wiring requires use of the above complicated processes, as a result, it is difficult to reduce cost and manufacturing process.

SUMMARY OF THE DISCLOSURE

The disclosure is directed to a circuit structure, which has a simple manufacturing process and low cost.

According to an embodiment of the present disclosure, a circuit structure includes a first flexible insulating layer, a plurality of wires, and a second flexible insulating layer. The wires are stacked in parallel on the first flexible insulating layer. The second flexible insulating layer is stacked on the wires and has at least one insulating-layer opening from which a part of at least one of the wires is exposed.

In the circuit structure according to the embodiment of the present disclosure, the wires include a first wire and a second wire adjacent to each other, and the first wire and the second wire are connected at a portion not covered by the first flexible insulating layer and the second flexible insulating layer. At least one of the first wire and the second wire has at least one wire opening corresponding to the at least one insulating-layer opening, and a part of the at least one of the first wire and the second wire is exposed from the at least one insulating-layer opening.

In the circuit structure according to the embodiment of the present disclosure, the circuit structure further includes at least one electronic component disposed in the at least one insulating-layer opening and electrically coupled to both ends of the at least one wire opening.

In the circuit structure according to the embodiment of the present disclosure, the wires include a first wire, a second wire, and at least one third wire between the first wire and the second wire. The at least one insulating-layer opening includes a first opening, a second opening and at least one third opening, the first wire is partially exposed from the first opening, the second wire is partially exposed from the second opening, and the at least one third wire is partially exposed from the at least one third opening.

In the circuit structure according to the embodiment of the present disclosure, the circuit structure further includes a first electronic component and a second electronic component. The at least one third opening includes two third openings. The first electronic component is electrically coupled to a portion of the first opening from which the first wire is exposed and a portion of one of the third openings from which the at least one third wire is exposed. The second electronic component is electrically coupled to a portion of the second opening from which the second wire is exposed and a portion of another one of the third openings from which the at least one third wire is exposed.

In the circuit structure according to the embodiment of the present disclosure, the first electronic component or the second electronic component is an electronic component having two pins, one of the first electronic component and the second electronic component is an active device, and the other is a passive device.

In the circuit structure according to the embodiment of the present disclosure, the first wire and the third wire electrically coupled to the first electronic component are adjacent or not adjacent to each other, and/or the second wire and the third wire electrically coupled to the second electronic component are adjacent or not adjacent to each other.

In the circuit structure according to the embodiment of the present disclosure, the circuit structure further includes a third electronic component. The at least one third opening includes a third opening. The third electronic component is electrically coupled to the portions of the first opening, the second opening, and the third opening from which the first wire, the second wire, and the third wire are exposed respectively.

In the circuit structure according to the embodiment of the present disclosure, the third electronic component is an electronic component having three pins.

In the circuit structure according to the embodiment of the present disclosure, the first wire and the third wire electrically coupled to the third electronic component are adjacent or not adjacent to each other, and/or the second wire and the third wire electrically coupled to the third electronic component are adjacent or not adjacent to each other.

In the circuit structure according to the embodiment of the present disclosure, at least two of the first opening, the second opening, and the at least one third opening communicate with each other.

In the circuit structure according to the embodiment of the present disclosure, the circuit structure is formed on a flexible flat cable, and the first flexible insulating layer is bonded with the wires through adhesive and the second flexible insulating layer is bonded with the wires through adhesive. The flexible insulating layer and the second flexible insulating layer are bonded together at a part where the wires are not provided.

The circuit structure of the present disclosure can directly laminate a plurality of parallel wires through the upper first flexible insulating layer and the lower second flexible insulating layer, and by providing an insulating-layer opening on the second flexible insulating layer, a part of the wires is exposed. In the circuit structure of the present disclosure, electronic components can be arranged in the area where the wires are exposed, such that the circuit structure provided with the wires arranged in parallel can be used as an FPC, thereby significantly reducing cost and manufacturing process.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are incorporated for further illustrating the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and together with the description serve to explain the principles of the disclosure.

FIG. 1A is a schematic top view of a circuit structure according to an embodiment of the present disclosure.

FIG. 1B is a schematic cross-sectional view of the circuit structure of FIG. 1A.

FIG. 2A is a schematic top view of a circuit structure according to another embodiment of the present disclosure.

FIG. 2B is a schematic cross-sectional view of the circuit structure of FIG. 2A.

FIG. 3A is a schematic top view of a circuit structure according to another embodiment of the present disclosure.

FIG. 3B is a schematic view of the circuit structure of FIG. 3A configured with electronic components.

FIG. 3C is a circuit diagram of the circuit structure of FIG. 3B.

FIG. 4 is a schematic top view of a partial circuit structure according to another embodiment of the present disclosure.

DESCRIPTION OF EMBODIMENTS

Reference will now be made in detail to the exemplary embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or similar parts.

FIG. 1A is a schematic top view of a circuit structure according to an embodiment of the present disclosure. FIG. 1B is a schematic cross-sectional view of the circuit structure of FIG. 1A. Please refer to FIG. 1A and FIG. 1B. In this embodiment, the circuit structure 100 includes a first flexible insulating layer 110, a plurality of wires 130, and a second flexible insulating layer 120. The wires 130 are stacked in parallel on the first flexible insulating layer 110. In this embodiment, the number of the wires 130 is four for exemplary purpose, but in other embodiments, the number of the wires 130 may be 26, 50, or 55. The number of the wires 130 is not limited to the above. In addition, in this embodiment, the wire 130 is, for example, a straight line, but in other embodiments, the wire 130 may also have one or more bends. For example, the wires 130 can be extended together in one direction and then bent in another direction together. The form of the wire 130 and the thickness relationship of the first flexible insulating layer 110, the plurality of wires 130, and the second flexible insulating layer 120 are not limited by the drawings.

The second flexible insulating layer 120 is stacked on the wires 130. The second flexible insulating layer 120 has at least one insulating-layer opening 122 which exposes a part of at least one of the wires 130. More specifically, in this embodiment, the second flexible insulating layer 120 has a plurality of insulating-layer openings 122, so that a partial area of two of the wires 130 is exposed. Certainly, the position of the insulating-layer opening 122 of the second flexible insulating layer 120, the number of exposed wires 130, and the size of the insulating-layer opening 122 are not limited by the drawings.

When manufacturing the circuit structure 100 of this embodiment, a flexible flat cable can be selected, and a cutting process such as laser or a hole-cutting tool can be used to cut one of the two insulating layers (second flexible insulating layer 120) of the flexible flat cable to form the insulating-layer opening 122, such that a partial area of the wire 130 is exposed. Subsequently, electronic components (not shown) can be configured by means of surface mount technology (SMT) in the exposed area of the wire 130 to use the flexible flat cable that originally can only connect two circuit boards as the FPC, thereby significantly reducing cost and manufacturing process.

In this embodiment, the circuit structure 100 is exemplified as a flexible flat cable. Through utilization of an adhesive (not shown), the first flexible insulating layer 110 is bonded with the wires 130 and the second flexible insulating layer 120 is bonded with the wires 130. The first flexible insulating layer 110 and the second flexible insulating layer 120 are bonded together at a part where the wires 130 are not provided. For example, from the viewing angle of FIG. 1A, the second flexible insulating layer 120 will be bonded with the underneath first flexible insulating layer 110 (FIG. 1B) at a position locating between any two adjacent wires 130 and an external position of at least one of the left and right two wires 130 on the outermost side of the extending direction of the wire 130. Therefore, the total thickness of a portion of the circuit structure 100 embedded with the wire 130 is greater than the total thickness of the portion where the wire 130 is not provided, such that the first flexible insulating layer 110 and the second flexible insulating layer 120 exhibit a fluctuating contour. Certainly, the present disclosure provides no limitation to the type of the circuit structure 100.

FIG. 2A is a schematic top view of a circuit structure according to another embodiment of the present disclosure. FIG. 2B is a schematic cross-sectional view of the circuit structure of FIG. 2A. Please refer to FIG. 2A and FIG. 2B. The main difference between the circuit structure 100 a of this embodiment and the circuit structure 100 of the previous embodiment is that, in this embodiment, the wires 130 a include a first wire 131 and a second wire 133 adjacent to each other. In this embodiment, the first wire 131 may be connected to a positive electrode, and the second wire 133 may be connected to a negative electrode, for example. The first wire 131 and the second wire 133 are connected together at a portion not covered by the first flexible insulating layer 110 and the second flexible insulating layer 120, so that the first wire 131 and the second wire 133 are conducted. For example, the first wire 131 and the second wire 133 may be connected through a copper wire 134. In other embodiments, the first wire 131 and the second wire 133 may also be connected through a bonding wire or a 0 ohm resistor.

As can be seen from FIG. 2B, in this embodiment, the second flexible insulating layer 120 has the insulating-layer opening 122, at least one of the first wire 131 and the second wire 133 has at least one wire opening 132 corresponding to the at least one insulating-layer opening 122, and a portion of at least one of the first wire 131 and the second wire 133 is exposed from the at least one insulating-layer opening 122. Specifically, the second wire 133 has at least one wire opening 132 corresponding to the at least one insulating-layer opening 122. The at least one wire opening 132 is smaller than the at least one insulating-layer opening 122, so that a portion of the second wire 133 on both sides of the at least one wire opening 132 is exposed from the at least one insulating-layer opening 122. In addition, the circuit structure 100 a further includes at least one electronic component 10 disposed in the at least one insulating-layer opening 122 and electrically coupled to the second wire 133. For example, two pads 12 and 14 of each electronic component 10 are respectively connected to two sides of the at least one wire opening 132 of the second wire 133.

Specifically, the second wire 133 has a plurality of wire openings 132 corresponding to the plurality of insulating-layer openings 122, and the circuit structure 100 a includes a plurality of electronic components 10, and any one of the electronic components 10 includes two pins that are respectively arranged on the second wire 133 and connected in series. The electronic component 10 is electrically coupled to two ends 138 and 139 of the wire opening 132. The electronic component 10 may be an active device, such as a light emitting diode, so that the circuit structure 100 a of this embodiment can be used as a circuit board or a bus bar of a backlight module. Certainly, the application of the circuit structure 100 a is not limited thereto. In addition, in other embodiments, the electronic component 10 may be a passive device, such as a resistor or an inductor or other electronic components with two pins, or may include multiple active devices and/or passive devices according to different applications of the circuit structure 100 a, and all of which belong to the scope of the present disclosure.

It should be noted that the circuit structure 100 a of this embodiment may be manufactured by punching to form an opening in the second flexible insulating layer 120 and the second wire 133 of the flexible flat cable. The size of the opening is close to the size of the wire opening 132. Thereafter, the opening on the second flexible insulating layer 120 is enlarged by laser or a hole-cutting tool and the like, and the insulating-layer opening 122 is formed to expose the portion of the second wire 133 beside the wire opening 132. Certainly, the manufacturing method of the circuit structure 100 a is not limited to the above.

FIG. 3A is a schematic top view of a circuit structure according to another embodiment of the present disclosure. Please refer to FIG. 3A. In this embodiment, the wires 130 b include at least one first wire 135, at least one second wire 136, and at least one third wire 137 disposed between the at least one first wire 135 and the at least one second wire 136. The first wire 135 may be, for example, connected to a positive electrode, the second wire 136 may be, for example, connected to a negative electrode, and the third wire 137 may be a jumper, for example.

The at least one insulating-layer opening includes a first opening 123, a second opening 124, and a third opening 125. The first wire 135 is partially exposed from the first opening 123, the second wire 136 is partially exposed from the second opening 124, and the third wire 137 is partially exposed from the third opening 125.

FIG. 3B is a schematic view of the circuit structure of FIG. 3A configured with electronic components. Please refer to FIG. 3B. In this embodiment, the circuit structure further includes at least one first electronic component 20 and at least one second electronic component 30. Viewing from the enlarged view of FIG. 3B with reference to FIG. 3A, the first electronic component 20 includes two pins (pads 22 and 24), which are correspondingly connected to portions of the first wire 135 and the third wire 137 exposed from the first opening 123 (see FIG. 3A) and one of the third openings 125 (see FIG. 3A). The second electronic component 30 also includes two pins (pads 32 and 34), which are correspondingly connected to portions of the second wire 136 and the third wire 137 exposed from the second opening 124 (see FIG. 3A) and another third opening 125 (see FIG. 3A). In this embodiment, the first wire 135 and the third wire 137 electrically coupled to the first electronic component 20 are adjacent to each other, and the second wire 136 and the third wire 137 electrically coupled to the second electronic component 30 are adjacent to each other. In another embodiment, the first wire 135 and the third wire 137 electrically coupled to the first electronic component 20 are not adjacent to each other, and/or the second wire 136 and the third wire 137 electrically coupled to the second electronic component 30 are not adjacent to each other. One of the first electronic component 20 and the second electronic component 30 is an active device, and the other is a passive device. In this embodiment, the first electronic component 20 is a passive device, such as a resistor, and the second electronic component 30 is an active device, such as a light emitting diode.

FIG. 3C is a circuit diagram of the circuit structure of FIG. 3B. Referring to FIG. 3C, in this embodiment, the first wire 135 is connected to the voltage source 52 (positive), and the second wire 136 is connected to the ground 54 (negative). The circuit structure 100 includes a plurality of first electronic components 20 and a plurality of second electronic components 30. The first electronic components 20 and the second electronic components 30 can be connected in parallel as shown in FIG. 3C through the circuit structure 100 of FIG. 3B.

According to the above embodiments, it can be obtained that the designer can choose whether to connect the first wire and the second wire according to the required connection mode (series or parallel), and form corresponding openings in the second flexible insulating layer 120 to configure electronic components. Of course, since the number of wires is limited in the embodiments of FIG. 3A-FIG. 3C, the method used accordingly to name the first wire, the second wire, and the third wire is not intended to limit the embodiment. In other words, if the circuit structure as a whole includes N wires, the wires can also be named as first wire, . . . m^(th) wire (wherein m is smaller than N), . . . , N^(th) wire in a sequence from top to bottom. As for the electronic components configured according to the requirements, which equally have two pins, depending on the different dimensions and sizes, the two wires selected for electrical coupling in the embodiment are not limited to two adjacent wires, that is, the first wire (one of the wires electrically coupled to the electronic component having two pins) may be the m−1^(th) wire, and the second wire (the other wire electrically coupled to the electronic component having two pins) may be the m+1^(th) wire and so on. In other words, this electronic component crosses the m^(th) wire, of course, the numbers used here for denotation are for illustrative purposes only.

It should be noted that in FIG. 3A, the first opening 123 and one of the third openings 125 may correspond to the positions of the two pads 22 and 24 of the first electronic component 20, and the second opening 124 and another third opening 125 may correspond to the positions of the two pads 32 and 34 of the second electronic component 30. In other embodiments, at least two of the first opening 123, the second opening 124, and the at least one third opening 125 of the second flexible insulating layer 120 may communicate with each other.

For example, the first opening 123 and the third opening 125 corresponding to the two pads 22 and 24 of the first electronic component 20 can be directly connected to form a larger opening, and the second opening 124 and the third opening 125 corresponding to the two pads 32 and 34 of the second electronic component 30 can be directly connected to form another larger opening. Such design allows the first electronic component 20 and the second electronic component 30 to be positioned directly in the two openings, thereby achieving the effect of reducing the height.

FIG. 4 is a schematic top view of a partial circuit structure according to another embodiment of the present disclosure. Please refer to FIG. 4. In this embodiment, the circuit structure includes a third electronic component 40. The third electronic component 40 has three pins, such as a metal-oxide-semiconductor field-effect transistor, but which is not intended to limit the scope of the present disclosure. Specifically, the first wire 135 may be connected to a positive electrode, the second wire 136 may be connected to a negative electrode, and the third wire 137 may be a control signal line, for example. The three pads 42, 44 and 46 of the third electronic component 40 are connected to the first wire 135, the second wire 136, and the third wire 137, respectively. In other words, the designer can form an insulating-layer opening according to the type of electronic components and the position of the pad, and use the wires as different signal lines.

In this embodiment, the first wire 135 and the third wire 137 electrically coupled to the third electronic component 40 are adjacent to each other, and/or the second wire 136 and the third wire 137 electrically coupled to the third electronic component are adjacent to each other. In an embodiment, the first wire 135 and the third wire 137 electrically coupled to the third electronic component 40 are not adjacent to each other, and/or the second wire 136 and the third wire 137 electrically coupled to the third electronic component 40 are not adjacent to each other.

That is to say, if the electronic component adopted has three pins, depending on their different dimensions and sizes, the three wires selected for electrical coupling in this embodiment are not necessarily three adjacent wires. In other words, a plurality of wires may be included between the two upper and lower wires, that is, the first wire may be the m−1^(th) wire, the second wire may be the m+2^(th) wire, and the third wire may be the m^(th) wire. Of course, the numbers used here for denotation are for illustrative purposes only.

Of course, according to different needs or designs, the foregoing multiple embodiments can be used in combination with each other, or other types of electronic components/modules having different numbers of pins can be selected. In this case, the present disclosure can apply the FPC to various types of circuit design and/or device and system, such as the circuit board used as the backlight module or application of flat cable for electrical coupling and so on but not limited thereto, by simply correspondingly adjust the number of applicable wires and the number of corresponding insulating openings.

The circuit structure of the present disclosure can directly laminate a plurality of parallel wires through the upper first flexible insulating layer and the lower second flexible insulating layer (or directly use a flexible flat cable), and by forming an insulating-layer opening in the second flexible insulating layer, a portion of the wires can be exposed. In the circuit structure of the present disclosure, electronic components can be arranged subsequently in the exposed areas of the wires, such that the circuit structure having the wires configured in a parallel manner can be used as a flexible circuit board, thereby significantly reducing cost and manufacturing process.

Finally, it should be noted that the above embodiments only serve to illustrate the technical solution of the present disclosure, but are not intended to be limiting. Although the present disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: the technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features can be equivalently replaced; and these modifications or replacements do not deviate the nature of the corresponding technical solutions from the scope of the technical solutions of the various embodiments of the present disclosure. 

What is claimed is:
 1. A circuit structure, comprising: a first flexible insulating layer; a plurality of wires stacked in parallel on the first flexible insulating layer; and a second flexible insulating layer stacked on the plurality of wires and having at least one insulating-layer opening from which a part of at least one of the plurality of wires is exposed.
 2. The circuit structure of claim 1, wherein the plurality of wires comprise a first wire and a second wire adjacent to each other, and the first wire and the second wire are connected at a portion not covered by the first flexible insulating layer and the second flexible insulating layer, and at least one of the first wire and the second wire has at least one wire opening corresponding to the at least one insulating-layer opening, and a part of the at least one of the first wire and the second wire is exposed from the at least one insulating-layer opening.
 3. The circuit structure of claim 2, further comprising at least one electronic component disposed in the at least one insulating-layer opening and electrically coupled to both ends of the at least one wire opening.
 4. The circuit structure of claim 1, wherein the plurality of wires comprise a first wire, a second wire, and at least one third wire disposed between the first wire and the second wire, the at least one insulating-layer opening comprises a first opening, a second opening, and at least one third opening, the first wire is partially exposed from the first opening, the second wire is partially exposed from the second opening, the at least one third wire is partially exposed from the at least one third opening.
 5. The circuit structure of claim 4, further comprising a first electronic component and a second electronic component, wherein the at least one third opening comprises two third openings, and the first electronic component is electrically coupled to a portion of the first wire exposed from the first opening and a portion of the at least one third wire exposed from one of the third openings, the second electronic component is electrically coupled to a portion of the second wire exposed from the second opening and a portion of the at least one third wire exposed from another one of the third openings.
 6. The circuit structure of claim 5, wherein the first electronic component or the second electronic component is an electronic component having two pins, and one of the first electronic component and the second electronic component is an active device and the other is a passive device.
 7. The circuit structure of claim 5, wherein the first wire and the third wire both electrically coupled to the first electronic component are adjacent or not adjacent to each other, and/or the second wire and the third wire both electrically coupled to the second electronic component are adjacent or not adjacent to each other.
 8. The circuit structure of claim 4, further comprising a third electronic component, wherein the at least one third opening comprises a third opening, and the third electronic component is electrically coupled to portions of the first wire, the second wire and the third wire respectively exposed from the first opening, the second opening and the third opening.
 9. The circuit structure of claim 8, wherein the third electronic component is an electronic component having three pins.
 10. The circuit structure of claim 8, wherein the first wire and the third wire both electrically coupled to the third electronic component are adjacent or not adjacent to each other, and/or the second wire and the third wire both electrically coupled to the third electronic component are adjacent or not adjacent to each other.
 11. The circuit structure of claim 4, wherein at least two of the first opening, the second opening, and the at least one third opening communicate with each other.
 12. The circuit structure of claim 1, wherein the circuit structure is formed on a flexible flat cable, and through an adhesive the first flexible insulating layer is bonded with the plurality of wires and the second flexible insulating layer is bonded with the plurality of wires, and the first flexible insulating layer and the second flexible insulating layer are bonded together at a portion where the plurality of wires are not provided. 